1. Field of the Invention
The present invention relates to a light module intended to be arranged in a headlight of a vehicle, notably of a motor vehicle, and a headlight comprising such a light module.
2. Description of the Related Art
Traditionally, motor vehicles are equipped at the front with headlights suitable for forming light beams which are likely to fulfill different lighting functions taking into account traffic conditions, such as, for example, low beam, sidelight, high beam or even fog light functions.
Headlights are known from the prior art which are suitable for forming sophisticated light beams, also called adaptive, the dimensions, the intensity and/or the direction of which are adjusted to fulfill such functions. These headlights make it possible notably to produce directional, adaptive or glare-free high-beam light functions, comprising at least one zone for masking the beam in the zones where vehicles being overtaken or followed are situated.
Each headlight generally consists of a plurality of light modules that make it possible to obtain a light power that is sufficient to form a light beam. Each of these light modules then forms a part of the light beam of the headlight by being on or off separately relative to one another.
A “light module” should be understood to mean an assembly comprising at least one light source and one optical projection or reflection system.
When the light source is, for example, a laser source, the module can comprise a wavelength conversion device.
This laser light source of the light module is capable of emitting radiation toward a scanning system such as a micro-mirror movably mounted around two orthogonal axes. This radiation is then deflected by this scanning system to at least one wavelength conversion device which comprises a substrate made of reflective or transparent material on which is deposited a thin layer of phosphorescent material.
It will be noted in the present text that “photoluminescent material” should be understood to mean a material having a photo-luminescent effect, for example phosphorescent, generally comprising different chemical elements, but not necessarily containing phosphorus.
The conversion device, by thus being scanned by the scanning system, re-emits a white light radiation to an optical projection system and thus forms a part of the light beam of the headlight.
The modules of such a headlight are driven by a control unit which controls the activation of the laser light sources and the scanning systems to produce the different lighting functions of the headlight.
However, such a headlight, by thus comprising a plurality of light modules, is of significant bulk. Furthermore, it is costly and complex to design notably because it requires significant adjustment time and accurate parameterization of these light modules for the configuration of the different lighting functions.
What is more, such a headlight generally produces a light beam which can present different colors because each part of this beam is produced by each of these light modules and notably because of the variability of the layers of phosphorescent material from one module to another.
Furthermore, each light module with which this headlight is equipped is relatively ineffective compared to the nominal power of the laser sources: in effect, the rate of use of the power of the laser is low because, while it is being used, the laser is frequently underpowered to form a usual regulatory beam and avoid generating light spots in the beam which would not comply with the regulatory maxima. This is also necessary to avoid a visual nuisance for the driver, linked to an excessively strong lighting in proximity to the vehicle.